Methods and Arrangements for Managing Round Trip Time Associated with Provision of a Data Flow via a Multi-Access Communication Network

ABSTRACT

Methods and device(s) ( 110; 120; 130; 140; 141; 210; 212; 220; 230; 600 ) for managing Round Trip Time, RTT, associated with provision of a data flow ( 150; 250 ) from a server device ( 130; 230 ), via a multi-access communication network ( 100; 200 ), to a client device ( 120; 220 ). Said device(s) ( 110; 120; 130; 140; 141; 210; 212; 220; 230; 600 ) being communicatively connected to the multi-access communication network ( 100; 200 ) that is configured to provide the data flow ( 150; 250 ) to the client device ( 120; 220 ) using a resource of the multi-access communication network ( 100; 200 ) that is shared by multiple devices ( 120 - 121; 220 - 221 ). The device(s) ( 110; 120; 130; 140; 141; 210; 212; 220; 230; 600 ) initiates, in response to identification that the data flow ( 150; 250 ) belongs to a certain type, introduction of an artificial delay in the RTT.

TECHNICAL FIELD

Embodiments herein concern a method and arrangements relating tomanaging Round Trip Time, RTT, associated with provision of a data flowfrom a server device, via a multi-access communication network, e.g. atelecommunication network, to a client device.

BACKGROUND

Communication devices such as wireless communication devices, thatsimply may be named wireless devices, may also be known as e.g. userequipments (UEs), mobile terminals, wireless terminals and/or mobilestations. A wireless device is enabled to communicate wirelessly in awireless communication network, wireless communication system, or radiocommunication system, e.g. a telecommunication network, sometimes alsoreferred to as a cellular radio system, cellular network or cellularcommunication system. The communication may be performed e.g. betweentwo wireless devices, between a wireless device and a regular telephoneand/or between a wireless device and a server via a Radio Access Network(RAN) and possibly one or more core networks, comprised within thecellular communication network. The wireless device may further bereferred to as a mobile telephone, cellular telephone, laptop, PersonalDigital Assistant (PDA), tablet computer, just to mention some furtherexamples. Wireless devices may be so called Machine to Machine (M2M)devices or Machine Type of Communication (MTC) devices, i.e. devicesthat are not associated with a conventional user.

The wireless device may be, for example, portable, pocket-storable,hand-held, computer-comprised, or vehicle-mounted mobile device, enabledto communicate voice and/or data, via the RAN, with another entity, suchas another wireless device or a server.

The wireless communication network may cover a geographical area whichis divided into cell areas, wherein each cell area is served by at leastone base station, or Base Station (BS), e.g. a Radio Base Station (RBS),which sometimes may be referred to as e.g. “eNB”, “eNodeB”, “NodeB”, “Bnode”, or BTS (Base Transceiver Station), depending on the technologyand terminology used. The base stations may be of different classes suchas e.g. macro eNodeB, home eNodeB or pico base station, based ontransmission power and thereby also cell size. A cell is typicallyidentified by one or more cell identities. The base station at a basestation site may provide radio coverage for one or more cells. A cell isthus typically associated with a geographical area where radio coveragefor that cell is provided by the base station at the base station site.Cells may overlap so that several cells cover the same geographicalarea. By the base station providing or serving a cell is typically meantthat the base station provides radio coverage such that one or morewireless devices located in the geographical area where the radiocoverage is provided may be served by the base station in said cell.When a wireless device is said to be served in or by a cell this impliesthat the wireless device is served by the base station providing radiocoverage for the cell. One base station may serve one or several cells.Further, each base station may support one or several communicationtechnologies. The base stations communicate over the air interfaceoperating on radio frequencies with the wireless device within range ofthe base stations.

In some RANs, several base stations may be connected, e.g. by landlinesor microwave, to a radio network controller, e.g. a Radio NetworkController (RNC) in Universal Mobile Telecommunication System (UMTS),and/or to each other. The radio network controller, also sometimestermed a Base Station Controller (BSC) e.g. in GSM, may supervise andcoordinate various activities of the plural base stations connectedthereto. GSM is an abbreviation for Global System for MobileCommunication (originally: Groupe Spécial Mobile), which may be referredto as 2nd generation or 2G.

UMTS is a third generation mobile communication system, which may bereferred to as 3rd generation or 3G, and which evolved from the GSM, andprovides improved mobile communication services based on Wideband CodeDivision Multiple Access (WCDMA) access technology. UMTS TerrestrialRadio Access Network (UTRAN) is essentially a radio access network usingwideband code division multiple access for wireless devices. High SpeedPacket Access (HSPA) is an amalgamation of two mobile telephonyprotocols, High Speed Downlink Packet Access (HSDPA) and High SpeedUplink Packet Access (HSUPA), defined by 3GPP, that extends and improvesthe performance of existing 3rd generation mobile telecommunicationnetworks utilizing the WCDMA. Such networks may be named WCDMA/HSPA.

The expression downlink (DL) may be used for the transmission path fromthe base station to the wireless device. The expression uplink (UL) maybe used for the transmission path in the opposite direction i.e. fromthe wireless device to the base station.

In 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE),base stations, which may be referred to as eNodeBs or eNBs, may bedirectly connected to other base stations and may be directly connectedto one or more core networks. LTE may be referred to as 4th generationor 4G.

The 3GPP has undertaken to evolve further the UTRAN and GSM based radioaccess network technologies, for example into evolved UTRAN (E-UTRAN)used in LTE.

Work is ongoing with developing a next generation wide area networks,which may be referred to as NeXt generation (NX), New Radio (NR), orfifth generation (5G).

The RAN scheduler divides scarce radio resources between wirelesscommunication devices that e.g. are served by a base station of the RAN,e.g. all wireless communication devices that have something to send toand receive from servers on Internet. Consider traffic going from suchserver, or host, to a wireless communication device, corresponding to aclient, served by the RAN, for example traffic with data relating to websurfing, video etc. As long as the wireless communication device hassomething to be sent from the server, it will be scheduled by RAN. Thistakes resources.

To deliver traffic, i.e. data, from hosts, e.g. servers, to clients,e.g. wireless communication devices, in bursts, and in between bursts donot send anything at all, saves resources in the RAN, and reduces therisk that any shared resource(s) becomes overloaded. The temporary idletime between bursts can be used by RAN to e.g. deliver traffic foranother client, e.g. to another wireless communication device. This isespecially good when a cell and/or base station associated with theshared resource is congested.

SUMMARY

In view of the above, an object is to provide one or more improvementsin relation to the prior art, in particular to provide improvementsregarding delivery of data, from a host, e.g. a server, to clients, e.g.wireless communication devices, over a shared resource in a multi-accesscommunication network.

According to a first aspect of embodiments herein, the object isachieved by a method, performed by one or more devices, for managingRound Trip Time, RTT, associated with provision of a data flow from aserver device, via a multi-access communication network, to a clientdevice. Said one or more devices being communicatively connected to themulti-access communication network. The multi-access communicationnetwork being configured to provide the data flow to the client deviceusing a resource of the multi-access communication network that isshared by multiple client devices. Said one or more devices initiates,in response to identification that the data flow belongs to a certaintype, introduction of an artificial delay in the RTT.

According to a second aspect of embodiments herein, the object isachieved by a computer program comprising instructions that whenexecuted by a processing circuit causes the first node to perform themethod according to the first aspect.

According to a third aspect of embodiments herein, the object isachieved by a carrier comprising the computer program according to thesecond aspect.

According to a fourth aspect of embodiments herein, the object isachieved by one or more devices for managing RTT associated withprovision of a data flow from a server device, via a multi-accesscommunication network, to a client device. Said one or more devicesbeing configured to be communicatively connected to the multi-accesscommunication network. The multi-access communication network beingconfigured to provide the data flow to the client device using aresource of the multi-access communication network that is shared bymultiple client devices. Said one or more devices are further configuredto initiate, in response to identification that the data flow belongs toa certain type, introduction of an artificial delay in the RTT.

According to a fifth aspect of embodiments herein, the object isachieved by a method, performed by a server device, relating totransmission of a data flow towards a client device. The server deviceprovides data to be transported by the data flow. The server devicesinitiates transmission of the data flow comprising the provided data,towards the client device via a multiaccess communication network towhich one or more devices for managing RTT associated with provision ofthe data flow are communicatively connected. The multi-accesscommunication network being configured to provide the data flow to theclient device using a resource of the multi-access communication networkthat is shared by multiple client devices. Said one or more devicesbeing configured to initiate, in response to identification that thedata flow belongs to a certain type, introduction of an artificial delayin the RTT.

The artificial delay will thus result in a longer RTT than else wold bethe case. If the artificial delay is say X milliseconds (ms), e.g. theso called Retransmission TimeOut (RTO) or Probe TimeOut (PTO) will beextended, i.e. longer until timeout, based on X. The new timeout may beextended by a time that may correspond to X ms but not necessarily. As aresult it can take longer, e.g. X ms longer, before the server deviceconsiders data packets it has sent as part of the data flow to be lost,e.g. when no acknowledgment has been received before RTO. In otherwords, there will be more time that can be used to deliver other datausing the shared resource, e.g. to other of the multiple devices.Without the artificial delay there may be need for increased bufferingin the multi-access communication network and/or some real-time criticaldata may not be able to deliver in time and/or there would be moreretransmissions of data packets that would load the network and also theserver that e.g. provides the data, but without actually improving thesituation for the client device.

Embodiments herein are beneficially applied in combination withprovision of the data flow in bursts to the client device Thanks toembodiments herein and the artificial delay, bursts can be used or adelay between the bursts can be increased, e.g. with X ms or based on X,without causing retransmissions. The increase time between bursts can beused to communicate data to/from the other multiple devices, or otherdata to/from the client device, using the resource, and without causingoverload, resulting in e.g. data loss and/or retransmission and/ordeteriorated performance in data delivery.

Embodiments herein are further beneficially applied in combination withwireless communication networks, e.g. 5G networks, where the number ofdevices sharing resources often vary over time as user move and changelocation, change habits etc, and there is often a resource sharingsituation, where devices has to share a limited resource e.g. due tolimited capacity and e.g. bandwidth limitations at base stations forserving wireless communication devices.

When the server device performs the method according to the fifthaspect, e.g. for delivering a video streaming service to the clientdevice, advantages include that the server device may need to retransmitmore seldom than else would be the case, hence saving bandwidth andtransmission resources, e.g. reducing the risk of overloaded resourceand e.g. better streaming over RAN. The client device, and e.g. a userthereof that is using the video streaming service, may in turn, thanksto this, experience a higher quality of service when using the service,e.g. as provided by a video streaming service provider.

As understood from the above, embodiments herein enable more efficientuse of shared resource in multiple access networks and thus enableimproved serving of multiple devices using a shared resource in amultiple access network. Embodiments herein are further versatile bybeing compatible with different transport protocols, e.g. bothTransmission Control Protocol (TCP) and the so called QUIC protocol.

Embodiments herein thus provide improvements regarding the ability todeliver data from a host, e.g. a server, to clients, e.g. wirelesscommunication device, over a shared resource in a multi-accesscommunication network.

BRIEF DESCRIPTION OF THE DRAWINGS

Examples of embodiments herein are described in more detail withreference to the appended schematic drawings, which are brieflydescribed in the following.

FIG. 1 is a block diagram schematically depicting an example of a firstcommunication system to be used for discussing embodiments herein.

FIG. 2 is another block diagram schematically depicting an example of asecond communication system to be used for discussing embodiments herein

FIG. 3 depicts a combined signaling diagram and flowchart, to be used todiscuss embodiments herein.

FIG. 4 schematically illustrates an example of how data can betransmitted in data bursts.

FIG. 5 is a flowchart schematically illustrating embodiments of a firstmethod according to embodiments herein.

FIG. 6 is a schematic block diagram for illustrating embodiments of howone or more devices may be configured to perform the first method.

FIG. 7 is a flowchart schematically illustrating embodiments of a secondmethod according to embodiments herein.

FIG. 8 is a schematic drawing illustrating some embodiments relating tocomputer program and carriers thereof to cause device(s) to perform saidfirst method and related actions.

DETAILED DESCRIPTION

Throughout the following description similar reference numerals may beused to denote similar elements, units, modules, circuits, nodes, parts,items or features, when applicable. Features that appear only in someembodiments of what is shown in a figure, are typically indicated bydashed lines in the drawings.

Embodiments herein are illustrated by exemplary embodiments. It shouldbe noted that these embodiments are not necessarily mutually exclusive.Components from one embodiment may be tacitly assumed to be present inanother embodiment and it will be obvious to a person skilled in the arthow those components may be used in the other exemplary embodiments.

As a development towards embodiments herein, the situation indicated inthe Background will first be further elaborated upon.

The idle time between burst should at least not be greater than the socalled Retransmission Time Out (RTO), since if it greater the transportprotocol will assume that the packet is lost, re-transmit packet andchange congestion window, e.g. reduce sending rate to client. RTO(Retransmission Time Out) is used by dominating transport protocols suchas the Transmission Control Protocol (TCP) as a determining factor ofhow long a host, e.g. server, will wait before retransmitting thesegment that it has not received. Whenever a packet is sent, the sender,i.e. the host, sets a timer corresponding to the RTO, which is aconservative estimate of when that packet will be acknowledged (acked),i.e. latest the packet must be acknowledged. The timer is reset everytime the sender receives an acknowledgement. If the sender, i.e. host,does not receive an ack by then, it transmits that packet again, i.e.re-transmits it.

This problem is prominent in case of wireless communication networks,which typically has limited resources at fixed locations, e.g. at radiobase stations, which resources are shared by all wireless communicationsdevices in a proximity of each location at which the wirelesscommunication devices e.g. are served by a radio base station. Thewireless communication devices are in turn mobile with a number to beserved that changes over time and often and with varying trafficgeneration, both as a group and individually over time. This means thatthe RAN and e.g. a limited resource or resources in e.g. a base stationthereof, may be a bottleneck for communication in some situations andthis is a risk that of course is desirable to reduce.

The corresponding problem exists also in other multi-accesscommunication network configured to serve client devices with datatraffic using a resource that is shared by multiple client devices.

The TCP is one of the main protocols of the Internet protocol suite. Itoriginated in the initial network implementation in which itcomplemented the Internet Protocol (IP). Therefore, the entire suite iscommonly referred to as TCP/IP. TCP provides reliable, ordered, anderror-checked delivery of a stream of octets (bytes) betweenapplications running on hosts communicating via an IP network. Majorinternet applications such as the World Wide Web (WWW), email, remoteadministration, and file transfer rely on TCP. Applications that do notrequire reliable data stream service may use the User Datagram Protocol(UDP), which provides a connectionless datagram service that emphasizesreduced latency over reliability.

QUIC, pronounced ‘quick’, is a another transport layer network protocolinitially designed, implemented, and deployed in 2012 by Google. QUICwas originally an acronym for “Quick UDP Internet Connections”, but hassince evolved to be solely the name and no longer an acronym of theprotocol. A main goal of QUIC is to improve perceived performance ofconnection-oriented web applications that are currently using TCP. Itdoes this by establishing a number of multiplexed connections betweentwo endpoints over User Datagram Protocol (UDP). QUIC aims to be nearlyequivalent to a TCP connection but with much-reduced latency The IETF'sHTTP and QUIC Working Group have made an official request to rename theprotocol HTTP/3 in advance of making it a worldwide standard.

RTO is used by TCP and the corresponding timer is named Probe Timeout(PTO) in QUIC, both are used as determining factor of how long the hostwill wait before retransmitting.

RFC 6298 “Computing TCP's Retransmission Timer”, June 2011, describesRTO used by TCP, where chapter 2 describes the algorithm. It may benoted that one second is recommended as the lowest RTO value, but thisgas in many implementations have been changed to lower, e.g. 200 ms inLinux.

The document “QUIC Loss Detection and Congestion Controldraft-ietf-quic-recovery-18”, Jan. 23, 2019, section 6.2.2, describesPTO further.

The PTO is calculated similar to the RTO but the lowest value is notexplicitly defined a time value, but based on a clocking granularity ofthe host platform.

Calculation of RTO and PRO are dependent on the Round Trip Time (RTT) ofthe involved connection, e.g. between a server, or host, and client. RTTis a well-known concept in data networking but will be explained a bitfurther before proceeding. To explain it simple, the RTT measures thetime from sending a packet from the host to getting the acknowledgmentpacket from the target client.

Although a known concept in data communication and in particular for IPbased networks, RTT can in general be considered a time measure of howfast data can be delivered from a source or sender to a target orreceiver, including also an acknowledge of the receipt received by thesender. Further, this time measure may be one that controls for how longthe sender, after sending a data packet, will wait for suchacknowledgement until considering the data packet as lost and willretransmit it.

Moreover, with the replacement of TCP by QUIC, some existing solutionsto the “resource sharing” problem, that the bursts may be used toreduce, may no longer be working. It is also believed that the trendwith increased amount of data heavy flows, e.g. so called elephant flowsas will be further discussed below, e.g. from streaming mediaconsumption, will continue. In 5G networks, this kind of traffic willlikely be increasingly combined with communication to/from Internet ofThings (IoT) type of devices, and with a much larger total number ofdevices to share resource. Hence, it is desirable to come up with newsolutions to the resource sharing problem, in particular when/if QUICwill be used and for 5G networks.

An idea underlying embodiments herein is to artificially delay the RTTto thereby increase e.g. RTO or PTO, whereby greater time between burstscan be used without causing re-transmissions.

FIG. 1 is a block diagram schematically depicting an example of a firstcommunication system 10 to be used for discussing embodiments herein andin which embodiments herein may be implemented. The first communicationsystem 10 comprises a multi-access communication network 100 that may beor be based on an IP network, or in other words, a data communicationnetwork based on, such as implemented to support, the Internet Protocol,e.g. version 4 or version 6, i.e. IPv4 or IPv6. The figure shows a firstclient device 120 and a second client device 121 communicativelyconnected to the multi-access communication network 100, e.g. served byit and/or enable to receive and/or transmit data traffic via themulti-access communication network 100. The figure further shows aserver device 130, e.g. a host device, that for example provides datafor communication to/from the client devices 120, 121, such as media forstreaming, e.g. audio and/or video data, via the multi-accesscommunication network 100. The figure further schematically illustratesa data flow 150 from the server device 130, via the multi-accesscommunication network 100, to the client device 120. The data flow 150may comprise said data provided by the server device 130. As usedherein, multi-access communication network is a communication networkthat provides access to, e.g. serves, multiple client devices. This maybe accomplished by offering the client devices connections andcommunication to/from and/or via the multi-access communication network100 using one or more common resources of the multi-access communicationnetwork 100, where each resource may be shared by multiple clientdevices. For example, the first client device 120 may receive the dataflow through a resource of the multi-access communication network 100that is also used by the multi-access communication network 100 todeliver data to the second client device, which resource thus is sharedbetween the first device 120 and the second device 121. Such sharedresource(s) may pertain to a network node that both the first device 120and the second device 121 connect to or via to access the multi-accesscommunication network 100 and e.g. is use for communication of datato/from the multi-access communication network 100. However, the sharedresource(s) could additionally or alternatively be a resource associatedwith another network device or node located further upstream. In anycase, such shared resource may be a bottle neck and e.g. a resource thatmay be overloaded first in case of heavy or certain type of data trafficto/from the multiple devices over the multi-access communication network100, e.g. due to that a very large number of client devices access orattempt to access the multi-access communication network 100 using theresource.

The figure further shows a network device 110, e.g. corresponding to anetwork node, comprised in the multi-access communication network 100and located in the path of the data flow 150. The network device 110 isthus corresponding to a network node that the data flow 150 passesthrough in its passage or route through the multi-access communicationnetwork 100. The network device 110 may comprise said shared resource.However, note that the shared resource may alternatively be associatedwith another network node, e.g. one that said multiple client devicesconnect to for accessing the multi-access communication network 100. Asrealized by the skilled person, the multi-access communication network100, shown as a cloud in the figure, contains multiple interconnectednetwork nodes although not explicitly shown.

In the figure it is also shown a remote device 141, e.g. remote networknode, and a remote computer network 140 that the remote device 141 maybe part of or connected to The remote computer network 140 maycorrespond to a so called computer cloud, or simply cloud, providingcertain services. The remote device 141 and/or remote network 140 maye.g. be communicatively connected to the multi-access communicationnetwork 100 and e.g. the network device 110, as illustrated in thefigure.

FIG. 2 is a block diagram schematically depicting an example of a secondcommunication system 20 to be used for discussing embodiments herein andin which embodiments herein may be implemented. The second communicationsystem 20 comprises a wireless communication network 200, e.g. atelecommunication network. The wireless communication network 200 maycomprise a Radio Access Network (RAN) 201 part and a core network (CN)202 part. The wireless communication network 200 is typically atelecommunication network or system, such as a cellular communicationnetwork that supports at least one Radio Access Technology (RAT), e.g.LTE, or 4G, New Radio (NR) that also may be referred to as 5G.

The wireless communication network 200 comprises network nodes that arecommunicatively interconnected. The network nodes may be logical and/orphysical and are located in one or more physical devices. The wirelesscommunication network 200, typically the RAN 201, may comprise a radionetwork node 210, i.e. a network node being or comprising a radiotransmitting network node, such as base station, and/or that are beingor comprising a controlling node that controls one or more radiotransmitting network nodes. Said radio network node may e.g. becommunicatively connected, such as configured to communicate, over, orvia, a so called X2-U communication interface or communication link withother radio network nodes (not shown) comprised in the RAN.

Further, the wireless communication network 200, or rather the CN 202may comprise one or more core network nodes, e.g. a core network node212, such as a Packet GateWay (P-GW) in LTE/4G or User Plane Function(UPF) node in NR/5G, that may be communicatively connected, such asconfigured to communicate, over, or via, a communication interface orcommunication link, such as the so called so called S1-U, with radionetwork nodes of the RAN 201, e.g. with the radio network node 210.

S1-U, X2-U are IP/UDP based and are examples of user plane protocolsused in e.g. LTE and NR wireless communication networks. These userplane protocols can be considered to correspond to application layerprotocols in terms of a IP network in general.

Hence, the wireless communication network 200 can be considered to bebased on and/or comprise one or more IP networks. For example, the radionetwork node 210 may be communicatively connected, e.g. via X2-U, toanother radio network node in an IP network part of the RAN 201.Moreover, the network node 210 may be communicatively connected, e.g.via S1-U, to the core network node 212. This connection is in an IPnetwork of the wireless communication network 200 that connects the RAN201 and CN 202.

The wireless communication network 100, or specifically one or morenetwork nodes thereof, e.g. the network node 110, is typicallyconfigured to serve and/or control and/or manage one or more wirelesscommunication devices, such as a first communication device 220 and asecond communication device 221, in radio coverage areas, i.e. an areawhere radio coverage is provided for communication with one or morecommunication devices. The communication device 220 may alternatively benamed a wireless communication device, or simply wireless device, and itmay correspond to a User Equipment (UE). Each radio coverage may beprovided by and/or associated with a particular Radio Access Technology(RAT). The radio coverage may be radio coverage of a radio beam, thatsimply may be named a beam. As should be recognized by the skilledperson, a beam is a more dynamic and relatively narrow and directionalradio coverage compared to a conventional cell, and may be accomplishedby so called beamforming. A beam is typically for serving one or a fewcommunication devices at the same time, and may be specifically set upfor serving this one or few communication devices. The beam may bechanged dynamically by beamforming to provide desirable coverage for theone or more communication devices being served by the beam. There may bemore than one beam provided by one and the same network node.

The wireless communication network, e.g. the CN 202 thereof, may furtherbe communicatively connected to, e.g. via the core network node 212, andthereby e.g. 15 provide access for said communication device 220, to anexternal network 240, e.g. the Internet. The external network 240comprise and are connected to further network nodes, e.g. an externalnetwork node 230. External here refers to external vs. the wirelesscommunication network 200. The external network node 230 may e.g.correspond to a server providing service(s) to one or more otherinternet connected devices, e.g. the communication device 220 that maybe provided with access to the external network 230, such as theInternet, via the wireless communication network 200, e.g. specificallyvia the core network node 220 as mentioned above. The communicationdevice 220 may thus be communicatively connected, e.g. by means ofTCP/UDP/IP and an application layer protocol, via the wirelesscommunication network 200 and the external network 240, with theexternal network node 230. A data flow 250, as indicated in the figureby a dotted line, may e.g. be provided from the external network node230, via the external network 240 and the wireless communication network200, to the first communication device 220. The external network node230 may e.g. be a server providing a video streaming service accessedvia an application, or app, executing on the communication device 220. Asimilar situation could arise with another or the same communicationdevice that is connected to the Internet via a Local Area Network (LAN),e.g. a WiFi network at home, instead of to the wireless communicationnetwork 200, e.g. 5G, as discussed above.

In comparison with FIG. 1, the first communication device 220 may beconsidered to correspond to the first client device 120, the secondcommunication device 221 to the second client device 121, the wirelesscommunication network 200, possibly together with the external network240 to the, multi-access communication network 100, any one of the radionetwork node 210 and the core network node 212 may be considered tocorrespond to the network device 110, the external network node 230 tothe server device 130, and the data flow 250 to the data flow 150. InFIG. 2, the shared resource mentioned in connection with FIG. 1, wouldtypically be associated with the radio network node 210 and e.g. a RANscheduler thereof, and shared by e.g. the first and second communicationdevices 220, 221.

It may be noted that a server, e.g. a device or network node,corresponding to the server device 130 or the external network node 230or external network 240, in practice may correspond to one or morephysical nodes or devices, e.g. associated with a service through orfrom which the data flow, e.g. 150 or 250, is provided. The server mayalternatively be termed e.g. a host computer, a server system orcommunication system.

Attention is drawn to that FIG. 1 and FIG. 2 are only schematic and forexemplifying purpose and that not everything shown in the figured may berequired for all embodiments herein, as should be evident to the skilledperson. Also, a multi-access communication network and wirelesscommunication network that correspond(s) to the ones shown in thefigures will typically comprise several further device, network nodesand details, as realized by the skilled person, but which are not shownherein for the sake of simplifying.

FIG. 3 depicts a combined signaling diagram and flowchart, which will beused to discuss embodiments herein.

Embodiments herein may be implemented by and/or in one or more networknodes and/or devices, e.g. node in the user plane, such as a nodeproviding or participating in a User Plane Function and/or TrafficDetection Function (UPF/TDF), or be UPF and/or PGW and/or TDF node(s),or more generally one or more nodes involved in provision of a data flowfrom a server to a client, as exemplified and shown in FIG. 3 as aUPF/PGW/TDF block. Actions relating to the UPF/PGW/TDF block in thefigure may e.g. be performed by the network device 110, the radionetwork node 210 or the core network node 212, but may involve multiplenodes and devices as indicated in the figure.

In the following, in order to simplify, actions that in the figure areassociated with the UPF/PGW/TDF block will be described as beingperformed by the network device 110. Correspondingly, the actionsperformed by the client in the figure will be described as beingperformed by the first client device 120 and actions performed by theserver in the figure will be described as being performed by the serverdevice 130.

The actions below may be taken in any suitable order and/or be carriedout fully or partly overlapping in time when this is possible andsuitable.

Actions 301 a,b

The client device 120 initiates to set up and participate in setting upa data flow, e.g. the data flow 150, with the server device 130, e.g.over the multi-access communication network 100. The set-up flow maye.g. be a connection establishment, e.g. as in TCP, such as of the typecalled TCP SYN.

Action 302

In response to the set-up of the data flow 150 in the previous action,the network device 110 identifies the flow and may identify that it willor likely will become of a certain type, such as a so called elephantflow, or big flow.

In computer networking, an elephant flow is an extremely large (in totalbytes) continuous flow set up by a TCP (or other protocol) flow measuredover a network link. Elephant flows, though not numerous, can occupy adisproportionate share of the total bandwidth over a period of time. Itis not clear who coined “elephant flow”, but the term began occurring inpublished Internet network research in 2001 when the observations weremade that a small number of flows carry the majority of Internet trafficand the remainder consists of a large number of flows that carry verylittle Internet traffic (mice flows).

Actions 303 a,b

The server device 130 responds to the set-up of the data flow initiatedby the client in Actions 301 a,b, which involves communicating theresult back to the client, e.g. communicating a confirmation oracknowledgement that the data flow is or will be set-up, e.g. togetherwith some information about the data flow.

Action 304

In connection with actions 303 a,b and in response to the identificationin Action 302, the network device 110 may be involved in setting up thedata flow 150 with an artificial delay, e.g. involved in introduction ofan artificial delay in RTT between the server device 130 and the clientdevice 120. The network device 130 may e.g. proposedly delay a sequenceof data from the server, part of the data flow 150, X milliseconds (ms)to introduce the artificial delay. As explained above, this will have aneffect of increasing RTO or PTO, i.e. the server device 130 will “see”or set a higher RTO than else would be the case. For example, thenetwork device 110 may be involved in introducing an artificial delaythat is X ms, which may correspond to or be based on a desirable delaybetween bursts, as will be explained further below. It may be predefinedor predetermined, e.g. based on an algorithm used to calculate RTO orPTO, what effect a certain artificial delay of RTT will have on RTO andPTO. In the following it may be assumed that an artificial delay of X mswill have an effect of extending RTO or PTO with X ms as well, althoughthis may thus not necessarily be the case in practise, but may serve toillustrate the principle.

Action 305

In response to the set-up data flow 150, the server device 130 sendsdata flow segments of the data flow 150 towards the client device 120under influence of the RTO or PTO that was increased by the artificialdelay.

Acton 306

The data flow segments are received by the network device 110, e.g.since it is in the path of the data flow 150 through the multi-accesscommunication network 100. The network device 110 provides the receiveddata flow segments as bursts, or in other words, introduces a delay inthe transmission towards the client device so that the data flowsegments are transmitted further towards the client device 120 in or asbursts. The delay between bursts should be based on the artificialdelay, or in practice it may be that the artificial delay that is setbased on a required or desirable delay between bursts. The may e.g. besent data flow segments for Y ms and then no sending of data flowsegments for an idle time period that may be set based on X or as afunction of X, e.g. f(X) ms. That is, if not the same as the artificialdelay X, the idle time between bursts may be determined by X, e.g. beseen as a function of X, f(X), that is based on the influence theartificial delay has on how long the idle time between bursts can bewithout causing retransmission. The idle time period, e.g. f(X), shouldbe kept below what causes retransmissions.

Thanks to the artificial delay and thereby extended RTO and PTO, longerdelay between the bursts are possible without having to retransmit datadue to that retransmission timeout else would have occurred.

Action 306 or corresponding action, should be performed in a device ornetwork node that contains the shared resource that it is desirable tooffload temporarily by means of the bursts, or upstream from such deviceor network node. For example, in case of the of the second communicationsystem 20 in FIG. 2, the shared resource may be in the radio networknode 210, and Action 306 may be performed by e.g. in the core networknode 212. It may also be the core network node 212 that is involved inAction 304 or corresponding action introducing the artificial delay inthe RTT, but it could as well be another node or device in the path ofthe data flow 250 or node or device communicatively connected to a nodeor device in the path of the data flow 250, in principle any device ornetwork node with the ability to cause an artificial delay in the RTTfor the data flow 250.

Action 307

As a result from Action 306, the client device 120 receives the dataflow segments, and thus the data flow 150, in bursts.

To sum up a main idea underlying embodiment herein: Delay RTTartificially so that the server (and client) will have a higher RTT thannormal. This will lead to higher RTO and/or PTO. This makes it possibleto send elephant flows in burst with longer idle time between burstswithout having the risk of re-transmission and reduced congestionwindow.

FIG. 4 schematically illustrates an example of how data 401 of adataflow, e.g. of any of the data flows 150, 250, can be transmitted indata bursts 402 a-d. Note that data 401 in the figure is schematic, inpractice when data is received e.g. as in FIG. 3 by UPF/PGW/TDF from theserver, the data will vary and may look like 402 a-d but without theidle time in between. Then, when the data it is transmitted fromUPF/PGW/TDF towards the client, it may be as the data bursts 402 a-dwith idle time in between.

During a certain time period a shared resource in multi-accesscommunication network, e.g. associated with a RAN scheduler in the radionetwork node 220 in the multi-access communication network 200, may beable to transmit a maximum data amount 403 indicated by a dotted squarein the figure. The part of the maximum data amount 403 that is not usedby the data 401 transmitted as the bursts 402 a-d can be used fortransmitting other traffic, i.e. the white region within the dottedsquare indicating the maximum data amount during the time period mayrepresent other data 404 that can be transmitted using the sharedresource during the time period. The other data may e.g. containmultiple other kind of traffic and data flows, e.g. resulting from websurfing etc, and are typically associated with other receiving devicesthan the receiving device of the data 401.

The shared resource may e.g. be bandwidth limited so that at any giventime there is a maximum available data rate as indicated by thehorizontal dotted line in the figure. If the data 401 of any of the dataflows 150, 250 uses this shared resource during the time period, part ofthe maximal data amount will be used for transmitting the data 401during the time period. Most straightforward is of course be to transmitdata segments of the data 401 as soon as possible when they are receivedby any node in the path from the data source, e.g. from any of theserver device 130 or the external network node 230, to the recipient,e.g. any of first client device 120 or the first wireless communicationdevice 220. However, for reasons discussed above, this may result inthat there, during the time period, e.g. at certain time points duringit, may be an overload of the shared resource due to that the maximumavailable data rate is not sufficient for what is to be transmitted withresulting data loss and/or that some time critical data, that e.g. mustbe deliver in near real time cannot be delivered in time. This can besolved by transmitting the data 401 in bursts as illustrated. Althoughthe data at subperiods when the bursts are transmitted will allocatemore of the maximum available data rate, there will be time periods inbetween when the full maximum available data rate is not utilized fortransmitting the data 401 and thus fully available for transmittingother traffic than the data 401.

The bursts may e.g. as illustrated and exemplified above, be transmittedfor Y seconds, and then there may be a delay of f(X) seconds, duringwhich time other traffic may fully utilize the resource and e.g. themaximum available bandwidth.

Also as discussed above, embodiments herein and the artificial delay canbe used to have a longer idle period, e.g. f(X) between bursts, thanelse would be possible without causing retransmission of data, whichthen of course would further load the resource and contribute to theshared resource problem.

FIG. 5 is a flowchart schematically illustrating embodiments of a firstmethod according to embodiments herein. The method is for managing RTTassociated with provision of a data flow, e.g. the data flow 150 or 250,from a server device, e.g. corresponding to the server deice 130 or theexternal network node 230, via a multi-access communication network,e.g. relating to the multi-access communication network 100 or thewireless communication network 200, to a client device, e.g.corresponding to the first client device 120 or the first communicationdevice 220. The method may be performed by one or more devices, e.g.corresponding to the network device 110, the first client device 120,device(s) of the remote computer network 140, the remote device 141, theradio network node 210, core network node 212, first communicationdevice 220, external network node 230 or device(s) of the externalnetwork 240. To simplify the following, the network device 110 will bemainly be used as example for performing the method. In general,entities of FIG. 1 will be used as main examples in the following. Insome embodiments the method and actions thereof is performed by a systemcomprising several devices, and e.g. comprising at least relevant partsof the first or second communication system 10, 20. The one or modedevices, when more than a single device perform the method, may bereferred to as a system or arrangement, e.g. a control or supportsystem.

Said one or more devices, e.g. the network device 110, arecommunicatively connected to said multi-access communication network,e.g. 100. The multi-access communication network, e.g. 100, isconfigured to provide the data flow, e.g. 150, to said client device,e.g. the first client device 120, using a resource of said multi-accesscommunication network, e.g. 100, that is shared by multiple devices,e.g. shared by the first client device 120 and the second client device121. The shared resource may be such resource as discussed above.

Hence, the resource is shared by multiple devices, including e.g. theclient device 120, which devices may be considered served by and/oraccessing the multi-access communication network through the resource.

As should be understood the resource shared by the multiple devices istypically a resource that the multi-access communication network, e.g.100, uses for communication with the multiple devices, e.g. forproviding data to the multiple devices. The resource is typicallylimited and e.g. associated with a bandwidth that is shared between themultiple devices. The resource may further be associated with aparticular node or device of the multi-access communication network,e.g. a base station such as the radio network node 210, that serves themultiple devices, e.g. the first and second wireless communicationdevices 220, 221.

Action 501

Said one or more device, here the network device 110, initiates, inresponse to identification that the data flow, e.g. 150, belongs to acertain type, introduction of an artificial delay in the RTT.

Said certain type may be associated with data flows that are so calledelephant flow, i.e. elephant type of data flows, as mentioned above.Hence, said certain type may be associated with lower real timerequirements than other types of data flows using the resource buttransports substantially greater data amounts than said other types.

Said identification that the data flow, e.g. 150, may be based on aprovision of a measure of data amount carried by the data flow over acertain time period and determination that the measured data amount isgreater than a predefined data amount, e.g. indicated by a certainthreshold.

Hence, the identification may involve obtaining a measure and/or valueof the amount of data during a certain, e.g. predetermined time period,and this measure may be compared to a certain, e.g. predetermined,threshold value. If it is greater than the threshold value, the dataflow may be identified as of said certain type, e.g. being an elephantflow.

It may alternatively or additionally be so that the identification maybe based on an IP-address or Server Name Indication (SNI), of the senderof the data flow, e.g. server, e.g. the server device 130. It may e.g.be known that certain IP-address(es) or SNI(s) indicate, e.g., is usedto carry, an elephant flow. For example, the identification of the dataflow as above based on provision of a measure, may result in anIP-address or SNI, which then may be used for the identification.

Initiate identification may include that other device(s) or networknode(s) is triggered to perform the actual identification. However, someembodiments, the identification is performed by the same device(s) ornode(s) performing the present action. For example, the network device110 may e.g. send some information about the data flow 150 to the remotedevice 141 and/or to the remote computer network 140, which performs theactual identification.

Said identification may comprise identification during set up of thedata flow, e.g. as discussed above in relation to FIG. 3. However, themethod may additionally or alternatively be performed after set up ofthe data flow, e.g. if it turns out there is a need to apply the method.Hence, to start with the data flow, e.g. 150, may be provided withoutinfluence of embodiments herein, but in case it become desirable orneeded to increase idle time between bursts to avoid retransmissions,embodiments herein may be applied and the artificial delay be introducedin the RTT.

That is, it may be sensed, or this may be already available informationin e.g. a RAN scheduler, if the resource is congested or risk to becongested. With reference to FIG. 4, there may be indication of trafficand data to be delivered using the resource that will or risk tooverload the resource, e.g. so the maximum available data rate at somepoint in time will or risk to be insufficient, e.g. due to that the data401, as part of the data flow 150, would use part of the data rate. Theartificial delay may enable increased idle time between the data bursts402 a-d, whereby this may offload the resource. It need not be the sameartificial delay used all the time, instead it may depend, e.g. be basedon, how utilized the resource is and/or is about to be, e.g. based oninformation in e.g. the RAN scheduler, e.g. regarding congestion, suchas congestion level. This means that the artificial delay may changeover time depending on utilization degree of the resource. Hence, theartificial delay may be based on, e.g. be set or be determined based on,a utilization degree of said resource.

The artificial delay may be in an order of a few hundred milliseconds,such as from 100 ms up to e.g. 500 ms. This may be the case in aninitial phases of a connection where a default RTO typically may be setto one second. However, shorter and longer artificial delays than thiscannot be ruled out in some situations. This action may fully or partlycorrespond to Action 304.

Action 502

Said one or more devices, e.g. the network device 110, may also initiateprovision of said data flow, e.g. 150, to, or towards, the clientdevice, e.g. 120, in bursts, e.g. the bursts 402 a-d, with an idle timebetween the bursts based on the artificial delay.

As should be realized from the above, the artificial delay will thusresult in a longer RTT, or similar measure, than else wold be the case.If e.g. the artificial delay is X s, e.g. the RTO or PTO will beextended, i.e. longer until timeout, based on X or as a function of X,e.g. corresponding to but not necessarily X s longer.

Hence, this enables or has the effect that it will take longer, e.g. X slonger, before e.g. the server device 130 considers data packets it hassent as part of the data flow 150 to be lost. Such effect is obtainedparticularly when the data flow transport is based on IP and TCP orQUIC, or any protocol that uses a retransmission timeout similar to theRTO or PTO, based on RTT or a corresponding measure. In other words,embodiments herein enable more time that can be used to deliver otherdata using the shared resource, e.g. to other of the multiple devicesthat share the resource. Without the artificial delay there may be needfor increased buffering, e.g. in the multi-access communication network100 and/or some real-time critical data may not be able to be deliveredin time to some client device(s) and/or there would be moreretransmissions of data packets that would load the multi-accesscommunication network 100 and also e.g. a server, e.g. the server device130, that provides the data, but without that this would actuallyimprove anything.

Embodiments herein are beneficially applied in combination withprovision of the data flow in bursts to the client, as exemplifiedabove. Thanks to embodiments herein and the artificial delay, the delaybetween the bursts can be increased, e.g. with X s, without causingretransmissions. The increased time between bursts can be used tocommunicate data to/from the other multiple devices, or other datato/from the client device, using said resource that is shared, andwithout causing overload, resulting in e.g. data loss and/orretransmission and/or deteriorated performance in data delivery.Embodiments herein may thereby e.g. free up RAN resources for otherflows and thus provide better RAN utilization.

Embodiments herein are further beneficially applied in combination withwireless communication networks, e.g. 5G networks, where the number ofdevices sharing resources often vary over time as user move and changelocation, change habits etc, and there is often a resource sharingsituation, where devices has to share a limited resource e.g. due tolimited capacity and e.g. bandwidth limitations in the RAN, e.g. at basestations, for serving wireless communication devices.

This action may fully or partly correspond to Action 306

FIG. 6 is a schematic block diagram for illustrating embodiments of howone or more devices 600, e.g. said one or more devices discussed abovein connection with FIG. 5, including e.g. the network device 110, may beconfigured to perform the method and actions discussed above inconnection with FIG. 5.

Hence, the device(s) 600 is for managing RTT associated with provisionof said data flow, e.g. 150, from said server, e.g. the server device130, via said multi-access communication network, e.g. 100, to saidclient device, e.g. the first client device 120. Said device(s) 600being configured to be communicatively connected to said multi-accesscommunication network. The multi-access communication network beingconfigured to provide said data flow, e.g. 150, to said client device,e.g. the network device 120, using a resource of the multi-accesscommunication network that is shared by said multiple devices, e.g. thefirst and second client devices 120, 121.

The device(s) 600 may comprise a processing module 601, such as a means,one or more hardware modules, including e.g. one or more processors,and/or one or more software modules for performing said method and/oractions.

The device(s) 600 may further comprise memory 602 that may comprise,such as contain or store, a computer program 603. The computer program603 comprises ‘instructions’ or ‘code’ directly or indirectly executableby the device)(s) 600 to perform said method and/or actions. The memory602 may comprise one or more memory units and may further be arranged tostore data, such as configurations and/or applications involved in orfor performing functions and actions of embodiments herein.

Moreover, the device(s) 600 may comprise a processor(s) 604, i.e. one ormore processors, as exemplifying hardware module(s) and may comprise orcorrespond to one or more processing circuits. In some embodiments, theprocessing module(s) 601 may comprise, e.g. ‘be embodied in the form of’or ‘realized by’ processor(s) 604. In these embodiments, the memory 602may comprise the computer program 603 executable by the processor(s)604, whereby the device(s) 600 is operative, or configured, to performsaid method and/or actions thereof.

Typically the device(s) 600, e.g. the processing module(s) 601,comprises Input/Output (I/O) module(s) 605, configured to be involvedin, e.g. by performing, any communication to and/or from other unitsand/or devices, such as sending and/or receiving information to and/orfrom other devices, e.g. receiving from the server device 130 andsending towards first client device 120. The I/O module(s) 605 may beexemplified by obtaining, e.g. receiving, module(s) and/or providing,e.g. sending, module(s), when applicable.

Further, in some embodiments, the device(s) 600, e.g. the processingmodule(s) 601, comprises one or more of an initiating module(s),providing module(s), and identifying module(s), as exemplifying hardwareand/or software module(s) for carrying out actions of embodimentsherein. These modules may be fully or partly implemented by theprocessor(s) 604.

The device(s) 600, and/or the processing module(s) 601, and/or theprocessor(s) 604, and/or the I/O module(s) 605, and/or the initiatingmodule(s) may thus be operative, or configured, to initiate, in responseto said identification that the data flow, e.g. 150, belongs to saidcertain type, introduction of the artificial delay in the RTT.

Further, the device(s) 600, and/or the processing module(s) 601, and/orthe processor(s) 604, and/or the I/O module(s) 605, and/or theinitiating module(s) may be operative, or configured, to initiate saidprovision of said data flow, e.g. 150, to the client device, e.g. thefirst client device 120, in said bursts, e.g. the bursts 402 a-d, withsaid idle time between the bursts based on the artificial delay.

FIG. 7 is a flowchart schematically illustrating embodiments of a secondmethod according to embodiments herein. This method is relating totransmission of a data flow, e.g. the data flow 150 or 250, towards aclient device, e.g. the first client device 120 or the first wirelesscommunication device 220. The method is performed by a server device,e.g. corresponding to the server device 130 or the external network node230. The server device 130 will be used as main example in thefollowing.

Action 701

The server device 130 provides data for transport by the data flow 150,or the external network node 230 provides data for transport by the dataflow 250.

This action may correspond to that a service provider provides data,e.g. video data, available for access on the server device 130 by clientdevices, e.g. the first client device 120.

Action 702

The server device, e.g. corresponding to 130 or 230, initiatestransmission of the data flow, e.g. 150 or 250, comprising the provideddata, towards the first client device 120 via a multiaccesscommunication network, e.g. the multiaccess communication network 100 orthe wireless communication network 200, to which one or more devices formanaging RTT associated with provision of the data flow arecommunicatively connected. Said one or more devices may be the device600 discussed above in connection with FIG. 6. The multi-accesscommunication network is configured to provide the data flow to theclient device using a resource of the multi-access communication networkthat is shared by multiple devices, that is, as been discussed in theforegoing.

When the server device, e.g. corresponding to 130 or 230, performs thesecond method, e.g. for delivering a video streaming service to theclient device, advantages include that the server device may need toretransmit more seldom than else would be the case, hence savingbandwidth and transmission resources, e.g. reducing the risk ofoverloaded resource and e.g. better streaming over RAN. The clientdevice, and e.g. a user thereof that is using the video streamingservice, may in turn, thanks to this, experience a higher quality ofservice when using the service, e.g. as provided by a video streamingservice provider.

FIG. 8 is a schematic drawing illustrating some embodiments relating tocomputer program and carriers thereof to cause said device(s) 600discussed above to perform said first method and related actions. Thecomputer program may be the computer program 603 and comprisesinstructions that when executed by the processor(s) 604 and/or theprocessing module(s) 601, cause the device(s) 600 to perform asdescribed above. In some embodiments there is provided a carrier, ormore specifically a data carrier, e.g. a computer program product,comprising the computer program. The carrier may be one of an electronicsignal, an optical signal, a radio signal, and a computer readablestorage medium, e.g. a computer readable storage medium 801 asschematically illustrated in the figure. The computer program 603 maythus be stored on the computer readable storage medium 801. By carriermay be excluded a transitory, propagating signal and the data carriermay correspondingly be named non-transitory data carrier. Non-limitingexamples of the data carrier being a computer readable storage medium isa memory card or a memory stick, a disc storage medium such as a CD orDVD, or a mass storage device that typically is based on hard drive(s)or Solid State Drive(s) (SSD). The computer readable storage medium 801may be used for storing data accessible over a computer network 802,e.g. the Internet or a Local Area Network (LAN). The computer program603 may furthermore be provided as pure computer program(s) or comprisedin a file or files. The file or files may be stored on the computerreadable storage medium 801 and e.g. available through download e.g.over the computer network 802 as indicated in the figure, e.g. via aserver. The server may e.g. be a web or File Transfer Protocol (FTP)server. The file or files may e.g. be executable files for direct orindirect download to and execution on said device(s) 600 to make itperform as described above, e.g. by execution by the processor(s) 604.The file or files may also or alternatively be for intermediate downloadand compilation involving the same or another processor(s) to make themexecutable before further download and execution causing said device(s)600 to perform as described above. The computer program 603 may in someembodiments correspond to a computer program relating to said simulatorand/or computer game, when e.g. embodiments herein are integrated withinone and the same computer program.

Note that any processing module(s) and circuit(s) mentioned in theforegoing may be implemented as a software and/or hardware module, e.g.in existing hardware and/or as an Application Specific IntegratedCircuit (ASIC), a field-programmable gate array (FPGA) or the like. Alsonote that any hardware module(s) and/or circuit(s) mentioned in theforegoing may e.g. be included in a single ASIC or FPGA, or bedistributed among several separate hardware components, whetherindividually packaged or assembled into a System-on-a-Chip (SoC).

Those skilled in the art will also appreciate that the modules andcircuitry discussed herein may refer to a combination of hardwaremodules, software modules, analogue and digital circuits, and/or one ormore processors configured with software and/or firmware, e.g. stored inmemory, that, when executed by the one or more processors may make thenode(s) and device(s) to be configured to and/or to perform theabove-described methods and actions.

Identification by any identifier herein may be implicit or explicit. Theidentification may be unique in a certain context, e.g. in the wirelesscommunication network or at least in a relevant part or area thereof.

The term “network node” or simply “node” as used herein may as suchrefer to any type of node that may communicate with another node in andbe comprised in a communication network, e.g. IP network or wirelesscommunication network. Further, such node may be or be comprised in aradio network node (described below) or any network node, which e.g. maycommunicate with a radio network node. Examples of such network nodesinclude any radio network node, a core network node, Operations &Maintenance (O&M), Operations Support Systems (OSS), Self OrganizingNetwork (SON) node, etc.

The term “radio network node” as may be used herein may as such refer toany type of network node for serving a wireless communication device,e.g. a so called User Equipment or UE, and/or that are connected toother network node(s) or network element(s) or any radio node from whicha wireless communication device receives signals from. Examples of radionetwork nodes are Node B, Base Station (BS), Multi-Standard Radio (MSR)node such as MSR BS, eNB, eNodeB, gNB, network controller, RNC, BaseStation Controller (BSC), relay, donor node controlling relay, BaseTransceiver Station (BTS), Access Point (AP), New Radio (NR) node,transmission point, transmission node, node in distributed antennasystem (DAS) etc.

Each of the terms “wireless communication device”, “user equipment” and“UE”, as may be used herein, may as such refer to any type of wirelessdevice arranged to communicate with a radio network node in a wireless,cellular and/or mobile communication system, and may thus be referred toas a wireless communication device. Examples include: target devices,device to device UE, device for Machine Type of Communication (MTC),machine type UE or UE capable of machine to machine (M2M) communication,Personal Digital Assistant (PDA), iPAD, Tablet, mobile, terminals, smartphone, Laptop Embedded Equipment (LEE), Laptop Mounted Equipment (LME),Universal Serial Bus (USB) dongles etc.

While some terms are used frequently herein for convenience, or in thecontext of examples involving other a certain, e.g. 3GPP or otherstandard related, nomenclature, it must be appreciated that such term assuch is non-limiting

Also note that although terminology used herein may be particularlyassociated with and/or exemplified by certain communication systems ornetworks, this should as such not be seen as limiting the scope of theembodiments herein to only such certain systems or networks etc.

As used herein, the term “memory” may refer to a data memory for storingdigital information, typically a hard disk, a magnetic storage, medium,a portable computer diskette or disc, flash memory, random access memory(RAM) or the like. Furthermore, the memory may be an internal registermemory of a processor.

Also note that any enumerating terminology such as first device or node,second device or node, first base station, second base station, etc.,should as such be considered non-limiting and the terminology as suchdoes not imply a certain hierarchical relation. Without any explicitinformation in the contrary, naming by enumeration should be consideredmerely a way of accomplishing different names.

As used herein, the expression “configured to” may mean that aprocessing circuit is configured to, or adapted to, by means of softwareor hardware configuration, perform one or more of the actions describedherein.

As used herein, the terms “number” or “value” may refer to any kind ofdigit, such as binary, real, imaginary or rational number or the like.Moreover, “number” or “value” may be one or more characters, such as aletter or a string of letters. Also, “number” or “value” may berepresented by a bit string.

As used herein, the expression “may” and “in some embodiments” hastypically been used to indicate that the features described may becombined with any other embodiment disclosed herein.

In the drawings, features that may be present in only some embodimentsare typically drawn using dotted or dashed lines.

As used herein, the expression “transmit” and “send” are typicallyinterchangeable. These expressions may include transmission bybroadcasting, uni-casting, group-casting and the like. In this context,a transmission by broadcasting may be received and decoded by anyauthorized device within range. In case of unicasting, one specificallyaddressed device may receive and encode the transmission. In case ofgroup-casting, e.g. multicasting, a group of specifically addresseddevices may receive and decode the transmission.

When using the word “comprise” or “comprising” it shall be interpretedas nonlimiting, i.e. meaning “consist at least of”.

The embodiments herein are not limited to the above described preferredembodiments. Various alternatives, modifications and equivalents may beused. Therefore, the above embodiments should not be taken as limitingthe scope of the present disclosure, which is defined by the appendingclaims.

1-20. (canceled)
 21. A method, performed by one or more devices, formanaging Round Trip Time (RTT) associated with provision of a data flowfrom a server device, via a multi-access communication network, to aclient device; the one or more devices being communicatively connectedto the multi-access communication network; the multi-accesscommunication network being configured to provide the data flow to theclient device using a resource of the multi-access communication networkthat is shared by multiple client devices; the method comprising:initiating, in response to identification that the data flow belongs toa certain type, introduction of an artificial delay in the RTT.
 22. Themethod of claim 21, wherein the certain type is associated with lowerreal time requirements than other types of data flows using theresource, but that transports substantially greater data amounts thanthe other types.
 23. The method of claim 21, wherein the identificationof the data flow is based on a provision of a measure of data amountcarried by the data flow over a certain time period and determinationthat the measured data amount is greater than a predefined data amount.24. The method of claim 21, wherein the identification comprisesidentification during set up of the data flow.
 25. The method of claim21, wherein the method further comprises initiating provision of thedata flow to the client device in bursts, with an idle time between thebursts based on the artificial delay.
 26. The method of claim 21,wherein the artificial delay is based on a utilization degree of theresource.
 27. A non-transitory computer readable recording mediumstoring a computer program product for controlling one or more devicefor managing Round Trip Time (RTT) associated with provision of a dataflow from a server device, via a multi-access communication network, toa client device; the one or more devices being communicatively connectedto the multi-access communication network; the multi-accesscommunication network being configured to provide the data flow to theclient device using a resource of the multi-access communication networkthat is shared by multiple client devices; the computer program productcomprising program instructions which, when run on processing circuitryof the one or more devices, causes the one or more devices to: initiate,in response to identification that the data flow belongs to a certaintype, introduction of an artificial delay in the RTT.
 28. One or moredevices for managing Round Trip Time (RTT) associated with provision ofa data flow from a server device, via a multi-access communicationnetwork, to a client device; the one or more devices being configured tobe communicatively connected to the multi-access communication network;wherein the multi-access communication network is configured to providethe data flow to the client device using a resource of the multi-accesscommunication network that is shared by multiple client devices; the oneor more devices comprising: processing circuitry; memory containinginstructions executable by the processing circuitry whereby the one ormore devices are operative to: initiate, in response to identificationthat the data flow belongs to a certain type, introduction of anartificial delay in the RTT.
 29. The one or more devices of claim 28,wherein the certain type is associated with lower real time requirementsthan other types of data flows using the resource but that transportssubstantially greater data amounts than the other types.
 30. The one ormore devices of claim 28, wherein the identification of the data flow isbased on a provision of a measure of data amount carried by the dataflow over a certain time period and determination that the measured dataamount is greater than a predefined data amount.
 31. The one or moredevices of claim 28, wherein the identification comprises identificationduring set up of the data flow.
 32. The one or more devices of claim 28,wherein the instructions are such that the one or more devices areoperative to initiate provision of the data flow to the client device inbursts with an idle time between the bursts based on the artificialdelay.
 33. The one or more devices of claim 28, wherein the artificialdelay is based on a utilization degree of the resource.
 34. A method,performed by a server device, relating to transmission of a data flowtowards a client device, wherein the method comprises: providing data tobe transported by the data flow; and initiating transmission of the dataflow comprising the provided data, towards the client device via amulti-access communication network to which one or more devices formanaging Round Trip Time (RTT) associated with provision of the dataflow are communicatively connected; the multi-access communicationnetwork being configured to provide the data flow to the client deviceusing a resource of the multi-access communication network that isshared by multiple client devices; wherein the one or more devices areconfigured to initiate, in response to identification that the data flowbelongs to a certain type, introduction of an artificial delay in theRTT.
 35. The method of claim 34, wherein the certain type is associatedwith lower real time requirements than other types of data flows usingthe resource but that transports substantially greater data amounts thanthe other types.
 36. The method of claim 34, wherein the identificationof the data flow is based on a provision of a measure of data amountcarried by the data flow over a certain time period and determinationthat the measured data amount is greater than a predefined data amount.37. The method of claim 34, wherein the identification comprisesidentification during set up of the data flow.
 38. The method of claim34, wherein the one or more devices are further configured to initiateprovision of the data flow to the client device in bursts with an idletime between the bursts based on the artificial delay.
 39. The method ofclaim 34, wherein the artificial delay is based on a utilization degreeof the resource.